1 files changed, 138 insertions, 0 deletions
diff --git a/busybox/coreutils/head.c b/busybox/coreutils/head.c
new file mode 100644
index 0000000..dab4de1
--- /dev/null
+++ b/busybox/coreutils/head.c
@@ -0,0 +1,138 @@
+/* vi: set sw=4 ts=4: */
+/*
+ * head implementation for busybox
+ *
+ * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/* BB_AUDIT SUSv3 compliant */
+/* BB_AUDIT GNU compatible -c, -q, and -v options in 'fancy' configuration. */
+/* http://www.opengroup.org/onlinepubs/007904975/utilities/head.html */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <ctype.h>
+#include <unistd.h>
+#include "busybox.h"
+
+static const char head_opts[] =
+	"n:"
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+	"c:qv"
+#endif
+	;
+
+static const char header_fmt_str[] = "\n==> %s <==\n";
+
+int head_main(int argc, char **argv)
+{
+	unsigned long count = 10;
+	unsigned long i;
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+	int count_bytes = 0;
+	int header_threshhold = 1;
+#endif
+
+	FILE *fp;
+	const char *fmt;
+	char *p;
+	int opt;
+	int c;
+	int retval = EXIT_SUCCESS;
+
+	/* Allow legacy syntax of an initial numeric option without -n. */
+	if ((argc > 1) && (argv[1][0] == '-')
+		/* && (isdigit)(argv[1][1]) */
+		&& (((unsigned int)(argv[1][1] - '0')) <= 9)
+	) {
+		--argc;
+		++argv;
+		p = (*argv) + 1;
+		goto GET_COUNT;
+	}
+
+	while ((opt = getopt(argc, argv, head_opts)) > 0) {
+		switch(opt) {
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+			case 'q':
+				header_threshhold = INT_MAX;
+				break;
+			case 'v':
+				header_threshhold = -1;
+				break;
+			case 'c':
+				count_bytes = 1;
+				/* fall through */
+#endif
+			case 'n':
+				p = optarg;
+			GET_COUNT:
+				count = bb_xgetularg10(p);
+				break;
+			default:
+				bb_show_usage();
+		}
+	}
+
+	argv += optind;
+	if (!*argv) {
+		*--argv = "-";
+	}
+
+	fmt = header_fmt_str + 1;
+#ifdef CONFIG_FEATURE_FANCY_HEAD
+	if (argc - optind <= header_threshhold) {
+		header_threshhold = 0;
+	}
+#else
+	if (argc <= optind + 1) {
+		fmt += 11;
+	}
+	/* Now define some things here to avoid #ifdefs in the code below.
+	 * These should optimize out of the if conditions below. */
+#define header_threshhold   1
+#define count_bytes         0
+#endif
+
+	do {
+		if ((fp = bb_wfopen_input(*argv)) != NULL) {
+			if (fp == stdin) {
+				*argv = (char *) bb_msg_standard_input;
+			}
+			if (header_threshhold) {
+				bb_printf(fmt, *argv);
+			}
+			i = count;
+			while (i && ((c = getc(fp)) != EOF)) {
+				if (count_bytes || (c == '\n')) {
+					--i;
+				}
+				putchar(c);
+			}
+			if (bb_fclose_nonstdin(fp)) {
+				bb_perror_msg("%s", *argv);	/* Avoid multibyte problems. */
+				retval = EXIT_FAILURE;
+			}
+			bb_xferror_stdout();
+		}
+		fmt = header_fmt_str;
+	} while (*++argv);
+
+	bb_fflush_stdout_and_exit(retval);
+}